The PI of this application is a physician-scientist with a career focus on developing improved care for patients with sickle cell disease (SCD). The acute chest syndrome (ACS) represents a serious, potentially fatal inflammatory lung injury syndrome occurring in patients with SCD. ACS shares many features of the inflammatory lung injury associated with acute lung injury and is the second most common cause of SCD hospitalization; is a major cause of acute and chronic SCD morbidity and mortality, is the leading cause of SCD ICU admission and premature death. There is increasing appreciation that ACS is an acute hypoxia-induced lung injury syndrome targeting the lung endothelium in response to multiple exogenous insults or triggers leading to pulmonary erythrocyte sequestration, an exaggerated inflammatory response, increased expression of adhesion molecules and impairment of pulmonary vascular function. In this highly translational proposal we will address the hypothesis that vascular-targeted genetic and genomic strategies for ACS will lead to better understanding of the pathobiology of ACS, generate novel ACS biomarkers in SCD patients and produce vascular-specific therapies for ameliorating this devastating health disparity. To address this hypothesis, in Specific Aim #1 we will identify novel single nucleotide polymorphisms that modulate ACS susceptibility and generate an ACS risk- conferring SNP panel. Specific Aim #2 will refine and validate genome-wide, vascular-centric genomic of ACS risk in SCD patients. In Specific Aim #3 we will interrogate the involvement of vascular permeability-regulatory pathway genes and proteins in murine ACS and ALI. Together, these highly translational approaches hold the promise to identify novel targets and biomarkers that may lead to better treatment options for patients with ACS.